Anti-collapsing tubes are sitting pretty in the cosmetics market thanks to a new system from carton and filling machine specialist Kalix.

Tubes produced on the Kalix machine have a ‘filled’ appearance with rounded corners. The system enables the use of more flexible tubes with thinner walls, making them cheaper. In addition, the length and width of the tubes remain the same for the same amount of product.

Kalix gets around the problem of shrinking that can be caused by hot air welding by using a slightly convex shaped weld. This helps to spread the longitudinal shrinkage forces across all the verticals between the weld and the tube shoulder, says the company.